Path: utzoo!attcan!utgpu!watmath!att!dptg!rutgers!usc!cs.utexas.edu!csd4.csd.uwm.edu!mailrus!ncar!ico!auto-trol!marbru
From: marbru@auto-trol.UUCP (Martin Brunecky)
Newsgroups: comp.windows.x
Subject: Re: getting CONTROL C  to interrupt X application
Message-ID: <261@auto-trol.UUCP>
Date: 30 Aug 89 22:41:56 GMT
References: <8908231747.AA20273@ATHENA.MIT.EDU> <525@granite.dec.com> <2395@auspex.auspex.com>
Reply-To: marbru@auto-trol.UUCP (Martin Brunecky)
Organization: Auto-trol Technology, Denver
Lines: 26

In article <2395@auspex.auspex.com> guy@auspex.auspex.com (Guy Harris) writes:
>>  I'm not sure if this is what you wanted,
>
>If he genuinely wanted an asynchronous interrupt, it's probably not. 
>The problem is that a polling strategy requires you to poll
>periodically.  Such a strategy may be implementable in many
>applications, and it may be implementable in his, though.
>

YES, polling is the only answer in the X world. One way of doing it is
to do your own XtMainLoop, i.e. call XtDispatchNextEvent explicitly.
But before this, you can always look if there is anything in the
queue, and if yes, you can look for a key event with control C in it.
When you find one, do whatever is appropriate - kill yourself, discard
the entire X queue etc. 
Be carefull about what X calls you use to scan the queue - you probbably
don't want to flush your output everytime you look for a control C.
Also, you may SCAN the queue for control C even when you are NOT going
to dispatch any event. 


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Martin Brunecky, Auto-trol Technology Corporation,
12500 North Washington Street, Denver, CO-80241-2404
(303) 252-2499                                        ncar!ico!auto-trol!marbru
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